Parasympathomimetics Flashcards
(50 cards)
Cholinergic agonist
Pupil constrict, heart decrease, vasodilation, bronchoconstriction, increase GI, urinary bladder constriction
Cholinergic receptor agonists chemicals
Acetylcholine, methacholine, carbachol, pilocarpine, betanechol
Acetylcholinesterase inhibitors
Edrophonium (tensilon), Physostigmine (Eserine), Neostigmine (prostigmin), Pyridostigmine (mestinon), Rivastigmine (excelon), Donepezil (aricept), Galantamine (razadyne), insecticides, nerve gases
Cholinergic receptor agonists info
Drugs that directly activate either nicotinic or muscarinic receptors
Many drugs that have anticholinergic activity effect?
patients with glaucoma, BPH, Alzheimer’s
Clinical uses of cholinergic receptor agonists
Very limited because of side effects
Open angle glaucoma
permits opening of canal of schlemm when ciliary muscle constricts for aqueous drainage, most common form, responds to therapy
Closed angle glaucoma
a physical obstruction of the canal, even muscle contraction the canal cannot be opened, does not respond to medication, can be emergency
Acetylcholinesterase Inhibitors
Blocks acetylcholinesterase will increase concentration of ACH in synapse, similar result of receptor agonist; increase GI, relax bladder sphincter
Adverse drug reactions of acetylcholinesterase inhibitors
SLUD; salivation, lacrimation, urination, defecation; increase sweating, bradycardia, hypotension, miosis
Adverse drug reactions of acetylcholinesterase inhibitors
SLUD; salivation, lacrimation, urination, defecation; increase sweating, bradycardia, hypotension, miosis
Eprophonium (tensilon)
rare, primarily used for diagnosis myasthenia gravis, given IV, short acting, pt with mg will have improvement when given this drug
pyridostigmine (Mestinon)
Reversible, for treatment of myasthenia gravis, PO
Neostigmine, Physostigmine
Used by anesthesiologists for reversal of neuromuscular blockers, IV or IM; reverse paraysis
Pralidoxime (Protam)
a cholinesterase reactivator, used for pesticide or nerve gas poisoning, most effective if given within hours of exposure, rarely used
Atropine
Given IV, can be used for reversal of any AchE inhibitor
Alzheimer’s disease
loss of cholinergic neuronal activity has been identified as a contributable cause of cognitive decline, AchE have become mainstay in therapy, hope to slow progression
Tacrine (Cognex)
first AchE inhibitor available, still on market but never used; causes liver damage
Tacrine (Cognex)
first AchE inhibitor available, still on market but never used; causes liver damage
Donepezil (aricept)
mild-severe alzheimer’s (dif dose), no dose adjust for hepatic or renal, ADR’s: incomnia, weight loss
Galantamine (Razadyne)
mild to moderate Alzheimer’s, PO only, dose adjust for renal and hepatic, Drug Interaction increase activity of galantamine
Rivastigmine (Exelon)
Mild-severe Alzheimer’s (same dose), Parkinson’s dementia (same dose), adjust for renal and hepatic; transdermal thought to be beneficial for compliance and less adr’s
Parasympatholytics are more commonly called
anticholinergics, very common
Action of anticholinergics
act as competitive antagonists at muscarinic receptor site on post ganglionic neurons
